A cyclone more powerful than any previously recorded in southern Oman slammed into the Gulf country and neighbouring Yemen, deluging a major city with nearly three years’ worth of rainfall in single day.

The storm killed at least six people while more than 30 remain missing, officials said.

Rushing waters from the rain and storm surges flooded typically dry creek beds. The holiday destination’s now-empty tourist beaches were littered with debris and foam from the churning Arabian Sea.

Three people, including a 12-year-old girl, died in Oman, and another two bodies were recovered from the Yemeni island of Socotra. More than 30 people were still missing in Socotra, including Yemeni, Indian and Sudanese nationals.

Yemeni officials also reported damage in the country’s far east, along the border with Oman. Rageh Bakrit, the governor of al-Mahra province, said on his official Twitter account late Friday that strong winds had blown down houses and taken out communication lines and water services. He said there were no fatalities in the province.

India’s Meteorological Department said the storm packed maximum sustained winds of 170-180 kilometres per hour with gusts of up to 200kph (124mph). It called the cyclone “extremely severe”.

Portions of Salalah, home to some 200,000 people, lost power as the cyclone made landfall.

On the outskirts of the city, near the Salalah International Airport, what once was a dry creek bed had become a raging river.

The airport, closed since Thursday, will reopen early Sunday, Oman’s Public Authority for Civil Aviation said.

The Port of Salalah – a key gateway for the country and for Qatar amid a regional diplomatic dispute – remained closed, its cranes secured against the pounding rain and winds.

Omani forecasters said Salalah and the surrounding area would get at least 200 millimetres (7.87 inches) of rain, over twice the city’s annual downfall. It actually received 278.2mm, nearly three times its annual rainfall.

Yemeni security officials said rescuers recovered two bodies on Socotra, while more than 30 people remain missing.

The island, listed by Unesco as a World Heritage Site, has been the focus of a dispute between the UAE and Yemen’s internationally recognised government, which are ostensibly allied against Shiite rebels known as Houthis.